Enhancing Bond Strength Of Medical Devices

ABSTRACT

Components of medical devices include polypropylene-poly(ethylene oxide) amphiphilic graft copolymers (PP-g-PEO) in their base polymer formulations. The base polymeric formulations comprise at least a polymer or co-polymer of propylene. These components are suitable for solvent-bonding with other components and enhance bond strength of the medical devices.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Application No.62/399,748, filed Sep. 26, 2016, the entire disclosure of which ishereby incorporated by reference herein.

TECHNICAL FIELD

Principles and embodiments of the present invention relate generally tomedical devices including polypropylene-poly(ethylene oxide) amphiphilicgraft copolymers (PP-g-PEO) in their base polymer formulations.Specifically, including PP-g-PEO in formulations for ethylene- and/orpropylene-containing polyolefin or thermoplastic elastomer (TPE) tubingenhances bonding strength between the tubing and connectors, where theconnectors are made of different materials compared to the tubing.

BACKGROUND

Medical tubing made from polyolefin (e.g., ethylene- orpropylene-containing) or thermoplastic elastomer (TPE) materials areused in, for example, infusion sets for delivery of intravenous (IV)fluids. Connectors are bonded to the tubing, thereby forming medicaldevices, which may be used alone or in conjunction with other medicaldevices to, for example, deliver fluids.

Solvent bonding is a technique used for joining molded plastic parts ofmedical devices. During the bonding process, the solvent dissolves thesurface of two mating parts and allows the material to flow together.Once the solvent evaporates, the result is a material-to-material bond.Many parts of medical devices made from plastics can be solvent-bondedin an application where ultrasonic bonding does not work. For dissimilarmaterials, however, solvent bonding does not typically achieve asatisfactory bonding. Namely, due to hydrophobicity and low surfaceenergy, the polyolefins and thermoplastic elastomers (TPEs) demonstratepoor interaction and solvent bonding with connector materials that aretypically made from poly(methyl methacrylate) (PMMA), styrene maleicanhydride (SMA), polycarbonate (PC), and methylmethacrylate-acrylonitrile-butadiene-styrene (MABS). For certainapplications such as an infusion kit with polypropylene orpolypropylene-containing-TPE tubing connected with a PMMA or SMA or PCor MABS connector, bonding performance between polypropylene or TPE andthe connector has not yet been acceptable. Solvents suitable for solventbonding processes include those solvents that can partially liquefyplastic along the joint and allow the joint to solidify causing apermanent chemical bonding. It is similar in end result to heat bondingmetal or thermoplastic. Bonded joints have an advantage over otheradhesives in that there is no third material creating the joint. Jointsare also airtight when created properly. Solvent bonding provides anadditional advantage in that it more readily integrates into rapidautomated assembly processes compared to more conventional adhesives,with a frequent cost advantage as well. Solvents suitable for solventbonding parts of medical devices are required to be non-flammable, notcarcinogenic, and not cause mechanical stress on the parts, an exampleof which is cyclohexanone.

Attempts have been made to improve bond strength. For example, U.S. Pat.No. 6,613,187 uses a cement composition comprising cyclicolefin-containing polymer and a solvent for solvent-bonding first andsecond polymeric materials. WO01/18112 also discloses a cementcomposition that is cyclic olefin containing polymer-based cementcomposition or bridged polycyclic hydrocarbon containing polymer-based.In addition, WO01/18112 discloses medical products that may besolvent-bonded, the products comprising homopolymers and/or copolymersof cyclic olefin containing polymers and bridged polycyclic hydrocarboncontaining polymers (collectively sometimes referred to as “COCs”). U.S.Pat. No. 6,649,681 uses a solvent-based adhesive to bond polymericfittings to components of articles used in medical applications. U.S.Pat. No. 6,673,192 uses cyanoacrylate adhesives activated with certainmulti-amine compounds to bond polyolefin substrates.

There is a continuing need to improve bond strength of medical devices.In particular, there is a need to improve bond strength of medicaldevices when bonding is done by a solvent, which is not flammable, notcarcinogenic, and does not cause mechanical stress of the parts. Due tothese solvent requirements, finding materials for components of medicaldevices that are suitable for solvent-bonding is an on-going challenge.

SUMMARY

Provided are components of medical devices, e.g., tubing, which exhibitenhanced bonding to other components, e.g., connectors.

Various embodiments are listed below. It will be understood that theembodiments listed below may be combined not only as listed below, butin other suitable combinations in accordance with the scope of theinvention.

A first aspect is a tubing for a medical device formed from a blendcomprising: a base polymeric formulation comprising at least a polymeror co-polymer of ethylene or propylene and excluding free poly(ethyleneoxide); and an additive comprising a polypropylene-poly(ethylene oxide)amphiphilic graft copolymer (PP-g-PEO); the PP-g-PEO being present inthe blend in an amount in the range of about 0.01 to about 5.0% byweight of the blend.

The base polymeric formulation may comprise polyethylene, polypropylene,a polypropylene-maleic anhydride co-polymer, apolyethylene-polypropylene co-polymer, a polyethylene- and/orpolypropylene-containing thermoplastic elastomer (TPE), or combinationsthereof. The base polymeric formulation comprises a co-polymer ofpolyethylene and polypropylene. The polyethylene- and/orpolypropylene-containing thermoplastic elastomer (TPE) comprises atleast 60 mol % total polyethylene and/or polypropylene. The PP-g-PEO maybe a product of ethylene oxide ring-opening polymerization of apolypropylene-maleic anhydride co-polymer (PP-MA) having from 10-50weight percent of maleic anhydride. In one or more embodiments, thePP-g-PEO is effective to enhance bonding of the tubing to a connector.

Another aspect is a medical device comprising: a tubing comprising apolymeric blend comprising a base polymeric formulation comprising atleast a polymer or co-polymer of ethylene or propylene and excludingfree poly(ethylene oxide), and an additive comprising apolypropylene-poly(ethylene oxide) amphiphilic graft copolymer(PP-g-PEO), wherein the PP-g-PEO is present in the blend in an amount inthe range of about 0.01 to about 5.0% by weight of the blend; and aconnector bonded to the tubing; wherein the PP-g-PEO is effective toenhance bonding of the tubing to a connector.

The base polymeric formulation may comprise polyethylene, polypropylene,a polyethylene-polypropylene co-polymer, a polyethylene- and/orpolypropylene-containing thermoplastic elastomer (TPE), or combinationsthereof. The base polymeric formulation may comprise a co-polymer ofpolyethylene and polypropylene. The polyethylene- and/orpolypropylene-containing thermoplastic elastomer (TPE) may comprise atleast 60 mol % polyethylene and/or polypropylene. The PP-g-PEO may be aproduct of ethylene oxide ring-opening polymerization of apolypropylene-maleic anhydride co-polymer (PP-MA) having from 10-50weight percent of maleic anhydride. The connector may comprise a polarmaterial. The polar material may be selected from the group consistingof: poly(methyl methacrylate) (PMMA), styrene maleic anhydride (SMA),polycarbonate (PC), and methylmethacrylate-acrylonitrile-butadiene-styrene (MABS). The connector maybe solvent-bonded to the tubing.

An additional aspect is a method of making a medical device comprising:obtaining a polypropylene-poly(ethylene oxide) amphiphilic graftcopolymer (PP-g-PEO); combining the PP-g-PEO with a base polymericformulation comprising at least a polymer or co-polymer of ethylene orpropylene and excluding free poly(ethylene oxide) to form a blend, thePP-g-PEO being present in the blend in an amount in the range of about0.01 to about 5.0% by weight of the blend; forming a tubing from theblend; bonding the tubing to a connector in the presence of a solvent toform the medical device; wherein the PP-g-PEO is effective to enhancebonding of the tubing to a connector.

Ethylene oxide ring-opening polymerization of a polypropylene-maleicanhydride co-polymer (PP-MA) having from 10-50 weight percent of maleicanhydride may be used to form the PP-g-PEO.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view illustrating a portion of an exemplary intravenous(IV) infusion kit comprising tubing, an IV injection port, andconnection; and

FIG. 2 provides a graph of bond strength (N) versus PP-g-PEOconcentration (weight %) for Comparative Example 1 (0%) and Examples 2-1(0.5%) and 2-2 (5.0%);

FIG. 3 is a graph of bond strength (N) versus PE concentration in anexemplary TPE base formulation, which used 0.5 wt.-% of PE-760-g-PEO-4as the additive in the base formulation;

FIG. 4 provides a graph of bond strength (N) versus PP-g-PEOconcentration (weight %) for Comparative Example 5 (0%) and Examples 6-1(0.5%) and 6-2 (5.0%);

FIG. 5 provides a graph of bond strength (N) versus PP-g-PEOconcentration (weight %) for Comparative Example 8 (0%) and Examples 9-1(0.5%) and 9-2 (5.0%).

DETAILED DESCRIPTION

Before describing several exemplary embodiments of the invention, it isto be understood that the invention is not limited to the details ofconstruction or process steps set forth in the following description.The invention is capable of other embodiments and of being practiced orbeing carried out in various ways.

The following terms shall have, for the purposes of this application,the respective meanings set forth below.

A base polymeric formulation is a material from which a medical devicemay be made. Preferably, the base polymeric formulations utilized inconjunction with the polypropylene-poly(ethylene oxide) amphiphilicgraft copolymers (PP-g-PEOs) disclosed herein comprise at least apolymer or co-polymer of propylene. Exemplary desirable base polymericformulations include but are not limited to polypropylene, systems suchas but not limited to polypropylene, polypropylene co-polymers includingbut not limited to a polypropylene-maleic anhydride co-polymer,polyethylene-polypropylene co-polymers, and/or polypropylene-containingthermoplastic elastomers (TPEs). The base formulation may furtherinclude other ingredients, independently selected from one or more ofthe following: reinforcing and non-reinforcing fillers, plasticizers,antioxidants, stabilizers, processing oil, extender oils, lubricants,antiblocking, antistatic agents, waxes, foaming agents, pigments, flameretardants and other processing aids known in the compounding art.Fillers and extenders which can be utilized include conventionalinorganics such as calcium carbonate, clays, silica, talc, titaniumdioxide, carbon black, and the like. The processing oils generally areparaffinic, naphthenic or aromatic oils derived from petroleumfractions. The oils are selected from those ordinarily used inconjunction with the specific plastics or rubbers present in theformulation.

Reference to polypropylene-poly(ethylene oxide) amphiphilic graftcopolymers (PP-g-PEO) means that a graft copolymer is formed by apolypropylene-containing monomer or prepolymer and poly(ethylene oxide),resulting in at least a polypropylene backbone and PEO side chains. Thepolypropylene-containing monomer or prepolymer may provide a desiredfunctionality or reactivity to accept side chains. Thepolypropylene-containing monomer or prepolymer may have a polypropylenebackbone with pendant groups suitable to receive PEO. A non-limitingexample of a polypropylene-containing prepolymer is a maleatedpolypropylene (also referred to as polypropylene-maleic anhydrideco-polymer) (PP-MA).

Reference to “free poly(ethylene oxide)” means poly(ethylene oxide) thatis not part of the polyethylene-poly(ethylene oxide) amphiphilic graftcopolymers.

As used herein the term “connector” is understood to include anystructure that is part of an intravenous device that is capable ofmaking a connection with a secondary intravenous device. Non-limitingexamples of connectors in accordance with the present invention includeneedleless connectors, male Luer connectors, female Luer connectors,side port valves, y-port valves, port valves, and other similarstructures. Connectors are preferably formed from polar materials, whichare those materials whose polymers have electrons that are notsymmetrically distributed resulting in polymers having slightly positivesections and slightly negative sections. Exemplary polar materialsinclude but are not limited to poly(methyl methacrylate) (PMMA), styrenemaleic anhydride (SMA), polycarbonate (PC), and methylmethacrylate-acrylonitrile-butadiene-styrene (MABS).

An additive is a component added to a formulation which is not reactivewithin the formulation.

Principles and embodiments of the present invention relate generally tomedical devices and components used therein made from a base polymericformulation to which an additive comprising apolypropylene-poly(ethylene oxide) amphiphilic graft copolymer(PP-g-PEO) is added via melt process but can be incorporated via othermechanisms such dissolving in a compatible solvent. Methods of makingand using these medical devices and components are also provided herein.

Embodiments of the present invention provide benefits over the priorart. For example, the disclosed invention here is a clean system in thatthere are no reactive agents involved in the process, which eliminatesany concerns of un-reacted agents or residuals, especially for medicalapplications. In addition, the traditional solvent bonding processremains the same in that no further step is needed, such as a step ofapplying adhesives, either solvent based adhesive or bulk adhesive.Further, low amounts of additive achieve enhanced bonding. That is, thecopolymer additive is present in the base polymeric formulation in anamount in the range of about 0.01 to about 5.0% by weight of the basepolymeric formulation of the medical device component (e.g., tubing),which is not expected to have any impact on the component's finalproperties or the process to make the components. The PP-g-PEO copolymerhas been designed to have an extremely hydrophobic segment PP and anextremely hydrophilic segment PEO. The PP-g-PEO copolymer enhanced theinterfacial bonding strength between PP and a second polymer like PMMA,SMA, PC, and MABS at a loading of 0.5 wt.-%.

PP-g-PEO graft copolymers have two kinds of segments. The PP segmentsare miscible with a polyolefin such as polypropylene, and the PEOsegments are miscible/compatible with second materials such as PMMA,SMA, PC, or MABS. When PP-g-PEO is melt blended with a polyolefin suchas polypropylene, due to the hydrophilicity of the PEO segment, thegraft copolymers tend to surge to the polymer surface and remain there,although at a low concentration or loading (for example, about 5 wt.-%or less, or about 1 wt.-% or less, or even about 0.5 wt.-% or less).This differentiates itself from other compatibilizer systems. Whensolvent bonding polyolefin (containing PP-g-PEO copolymers) with asecond material, the PP segments stay in the polyethylene side, whilethe PEO segments entangle, or adhere/interact, with the second material,PMMA, SMA, PC, or MABS. The PP-PEO graft copolymers work as a chemicalbridge connecting the otherwise immiscible polyethylene/second materialsand improve the interfacial bonding strength.

Typically, reactive blending/compatibilization is preferred due to itssuperiority in enhancing mechanical performance. For pre-madecopolymers, it would require minimum 5-10% loading by weight, in orderto achieve compatibilization or mechanical performance improvement. Forthe PP-g-PEO system, an amount of about 5 wt.-% or less of the copolymerto achieves significant increase on interfacial bonding strength, whichis unexpected. Without intended to be bound by theory, this can beexplained due to the fact that polypropylene (PP) present in tubingmaterial has extremely good miscibility with PP segments of the additiveand the same time it is immiscible with PEO segment that causesseparation of PEO segment from the dissimilar polymer matrix to thesurface.

General Procedure for Synthesis of PP-g-PEO & Preparation of Blend withBase Polymer Formulation

Polypropylene-poly(ethylene oxide) amphiphilic graft copolymers(PP-g-PEO) are additives for the base polymeric formulations ofcomponents of medical devices. These copolymers are also discussed inU.S. Pat. No. 9,150,674 to common assignee, which is incorporated hereinby reference. The process to make amphiphilic graft copolymers involvesgrafting poly(ethylene oxide) onto maleated polypropylene platform usingoxo-anion ring-opening polymerization chemistry. Polypropylene basedgraft copolymers are prepared starting from maleic anhydride graftedisotactic polypropylene. The amphiphilic character will result from theincorporation of hydrophilic poly(ethyleneoxide) (PEO) side-chains.

Preparation of amphiphilic polypropylene-based copolymers comprise:obtaining a maleic anhydride grafted polypropylene wherein the molarpercentages of grafted maleic anhydride units is in the range from 2 and10 mole percent; the molar values of propylene units is in the rangefrom 98 to 90 mole percent; reacting the maleic anhydride graftedpolypropylene with a reducing agent to prepare a iPP-diol copolymer,wherein the diol content is equal to the molar percentage of theoriginally grafted maleic anhydride units:

and subsequently performing ethylene oxide ring-opening polymerizationon the iPP-diol copolymer; and isolating an amphiphilic iPP-g-PEOcopolymer.

An exemplary PP-g-PEO copolymer is shown according to Formula (I).

wherein R represents the end-groups present in either Ziegler-Natta ormetallocene catalyzed polypropylene including, but not limited to,hydrogen, alkyl, substituted alkyl, vinylic substituted alkyl,hydrocarbyl, substituted hydrocarbyl, or vinylic substituted hydrocarbylgroup; the molar percentages of grafted maleic anhydride units, m, is inthe range from 2 to 10 mole percent; the molar values of propyleneunits, n, is in the range from 98 to 90 mole percent; and p is in therange of 5 to 500. The amount of diol after reduction of the maleicanhydride may be in the range from 2 to 10 mole percent.

The molar percentage value of propylene may be in the range of from 90to 98 mole percent, the molar percentage value of diol derived fromreduction of maleic anhydride may be in the range of from 10 to 2 molepercent, and the molar percentage value of p may be in the range of from5 to 400 mole percent.

In one or more embodiments, the ethylene oxide ring-openingpolymerization is performed at a reaction temperature in the range of−20 to 150° C. In a specific embodiment, the ethylene oxide ring-openingpolymerization is performed at a reaction temperature of greater than30° C. In another specific embodiment, the ethylene oxide ring-openingpolymerization is performed at a reaction temperature of 130° C.

The ethylene oxide ring-opening polymerization may performed underalkaline conditions. The ethylene oxide ring-opening polymerization maybe performed using 1,3 propane sultone and/or triethylamine.

In one or more embodiments, the amphiphilic iPP-g-PEO copolymer has adispersity index in the range of 2 to 8.

An exemplary PP-g-PEO copolymer composition is listed in Table 1.

TABLE 1 Exemplary PP-g-PEO copolymer Average Average —CH2—CH₂—CH₂— EOInterval Numbers Units in Nomenclature (Brush Density) Brush (PP-g-PEO)(n) (p) PP-g-PEO <1 45.5

Addition of the polypropylene-poly(ethylene oxide) amphiphilic graftcopolymer (PP-g-PEO) to the base polymeric formulation is done via meltprocessing. The term “melt processing” is used to mean any process inwhich polymers, such as the polyolefin, are melted or softened. Meltprocessing includes extrusion, pelletization, film blowing or casting,thermoforming, compounding in polymer melt form, fiber spinning, orother melt processes.

Any equipment suitable for a melt processing can be used as long as itprovides sufficient mixing and temperature control. For instance, acontinuous polymer processing system such as an extruder, a staticpolymer mixing device such as a Brabender blender, or a semi-continuouspolymer processing system, such as a BANBURY mixer, can be used. Theterm “extruder” includes any machine for polyolefin and TPE extrusion.For instance, the term includes machines that can extrude material inthe form of powder or pellets, sheets, fibers, or other desired shapesand/or profiles. Generally, an extruder operates by feeding materialthrough the feed throat (an opening near the rear of the barrel) whichcomes into contact with one or more screws. The rotating screw(s) forcesthe polyolefin forward into one or more heated barrels (e.g., there maybe one screw per barrel). In many processes, a heating profile can beset for the barrel in which three or more independentproportional-integral-derivative controller (PID)-controlled heaterzones can gradually increase the temperature of the barrel from the rear(where the plastic enters) to the front. When a melt extrusion is used,the mixing can take place during the melt extrusion step. The heatproduced during the extrusion step provides the energy necessary for themixing between different components. A temperature at or above themelting temperature of the polymer may be maintained for a timesufficient to mix all the components. For instance, the mixing time maybe at least 5 seconds, at least 10 seconds, or at least 15 seconds.Typically, the mixing time is 15-90 seconds.

Suitable blending temperature during melt mixing of polyolefins or TPEwith an additive should be sufficient to melt or to soften the componentof the composition which has the highest melting or softening point. Thetemperature typically ranges from 60 to 300° C., for instance, from 100to 280° C., from 90 to 150° C. One skilled in the art understands that apolyolefin or TPE mixtures thereof typically melts or softs over atemperature range rather than sharply at one temperature. Thus, it maybe sufficient that the polyolefin be in a partially molten state. Themelting or softening temperature ranges can be approximated from thedifferential scanning calorimeter (DSC) curve of the polyolefin ormixtures thereof.

TABLE 2 Exemplary Formulations (with the proviso that the ingredientstotal 100%). A B C Blend Ingredient by weight by weight by weight BasePolymeric   95-99.99%   95-99.99%   95-99.99% Formulation Polypropylene 50-100%  50-100%  50-100% Polyethylene  0-50%  0-50%  0-50%Propylene-containing  0-50%  0-50%  0-50% Thermoplastic elastomer (TPE)Optional further  0-10%  0-10%  0-10% ingredients Polypropylene-0.01-5%   0.01-5%   0.01-5%   poly(ethylene oxide) amphiphilic graftcopolymer (PP-g-PEO additive

In one or more embodiments, including Exemplary Formulations A, B, andC, the polypropylene-poly(ethylene oxide) amphiphilic graft copolymer(PP-g-PEO) additive may be present in amounts of about 0.01 to about5.0% by weight; about 0.1 to about 4.0% by weight; about 0.2 to about2.0% by weight; about 0.25 to about 0.75% by weight; or about 0.5 weight%.

Suitable polyethylene-polypropylene co-polymers may include—reactorgrade or melt blended mixtures of the polypropylene and polyethylenepolyolefins with or without polyolefin elastomers (final formulationcontaining from but not limited to about 10 wt.-% up to about 80 wt.-%ethylene and/or propylene monomeric units). The term “blend” or “polymerblend” generally refers to a mixture of two or more components. Such ablend may or may not be miscible, and may or may not be phase separated.

Suitable polyolefins include those prepared from linear or branchedolefins having 2 to 20 carbon atoms, 2 to 16 carbon atoms, or 2 to 12carbon atoms. Typically, the olefin used to prepare the polyolefin isα-olefin. Exemplary linear or branched α-olefins includes, but are notlimited to, ethylene, propylene, 1-butene, 2-butene, 1-pentene,3-methyl-1-butene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-hexene,3,5,5-trimethyl-1-hexene, 4,6-dimethyl-1-heptene, 1-octene, 1-decene,1-undecene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, and1-eicocene. These olefins may contain one or more heteroatoms such as anoxygen, nitrogen, or silicon. The term “polyolefin” generally embraces ahomopolymer prepared from a single type of olefin monomer as well as acopolymer prepared from two or more olefin monomers. A specificpolyolefin referred to herein shall mean polymers comprising greaterthan 50% by weight of units derived from that specific olefin monomer,including homopolymers of that specific olefin or copolymers containingunits derived from that specific olefin monomer and one or more othertypes of olefin comonomers. The polyolefin used herein can be acopolymer wherein the comonomer(s) is/are randomly distributed along thepolymer chain, a periodic copolymer, an alternating copolymer, or ablock copolymer comprising two or more homopolymer blocks linked bycovalent bonds. Typical polyolefins include polyethylene, polypropylene,a copolymer of polyethylene and polypropylene, and a polymer blendcontaining polyethylene, polypropylene, and/or a copolymer ofpolyethylene and polypropylene. Polyolefin can also be an ethylene richimpact copolymer (may contain ethylene comonomer at the amount of atleast 10 wt.-%; and up to 40 wt.-%), i.e., a heterophasic polyolefincopolymer where one polyolefin is the continuous phase and anelastomeric phase is uniformly dispersed therein. This would include,for instance, a heterophasic polypropylene copolymer where polypropyleneis the continuous phase and an elastomeric phase is uniformly dispersedtherein. The impact copolymer results from an in-reactor process ratherthan physical blending. The polyolefins mentioned above can be made byconventional Ziegler/Natta catalyst-systems or by single-sitecatalyst-systems.

Suitable polyolefin elastomers for use in the process of the inventioninclude styrene ethylene butylene styrene (SEBS)-based elastomers, whichinclude polypropylene. As used herein, the term “elastomer” refers toproducts having rubber-like properties and little or no crystallinity.Preferably, the polyolefin elastomers contain from about 10 wt.-% up toabout 80 wt.-% propylene monomeric units. Illustrative polyolefinelastomers which are commercially available include LanxessCorporation's BUNA EP T 2070 (22 Mooney ML(1+4) 125° C., 68% ethylene,and 32% propylene); BUNA EP T 2370 (16 Mooney, 3% ethylidene norbornene,72% ethylene, and 25% propylene); BUNA EP T 2460 (21 Mooney, 4%ethylidene norbornene, 62% ethylene, and 34% propylene); ExxonMobilChemical's VISTALON 707 (72% ethylene, 28% propylene, and 22.5 Mooney);VISTALON 722 (72% ethylene, 28% propylene, and 16 Mooney); and VISTALON828 (60% ethylene, 40% propylene, and 51 Mooney). Suitable EP elastomersavailable from commercial sources also include ExxonMobil Chemical'sVISTAMAXX series of elastomers, particularly VISTAMAXX grades 6100,1100, and 3000. These materials are ethylene-propylene elastomers of 16,15, and 11 wt.-% ethylene content, respectively, and a Tg of about −20to −30° C. VISTAMAXX 6100, 1100, and 3000, respectively, have a meltflow rate of 3, 4, and 7 g/10 min at 230° C.; a density of 0.858, 0.862,and 0.871 g/cm³; and a 200 g Vicat softening point of 48, 47, and 64° C.Other suitable elastomers include Dow Chemical's VERSIFYpropylene-ethylene copolymers, particularly grades DP3200.01, DP3300.01,and DP3400.01, which have nominal ethylene contents of 9, 12 and 15wt.-%, respectively, and corresponding nominal propylene contents of 91,88, and 85 wt.-%, respectively. These grades have a melt flow rate of 8g/10 min at 230° C.; a density of 0.876, 0.866, and 0.858 g/cm³,respectively; a Vicat softening point of 60, 29, and <20° C.,respectively; and a Tg of −25, −28, and −31° C., respectively.

Preferably, the polyolefin elastomers contain from but not limited toabout 10 wt.-% up to about 80 wt.-% propylene monomeric units. The term“thermoplastic elastomer” (TPE) in general defines blends of polyolefinsand rubbers in which blends of the rubber phase is not cured, i.e., socalled thermoplastic olefins (TPO), blends of polyolefins and rubbers inwhich blends of the rubber phase has been partially or fully cured by avulcanization process to form thermoplastic vulcanizates (TPV), orunvulcanized block-copolymers or blends thereof. Non-polar thermoplasticelastomer may made from a thermoplastic polyolefin homopolymer orcopolymer, and an olefinic rubber which is fully crosslinked, partiallycrosslinked or not crosslinked, and optionally commonly used additives;as well as a block-copolymer of styrene/conjugated diene/styrene and/orits fully or partially hydrogenated derivative.

Polyolefins suitable for use in TPE composition include thermoplastic,crystalline polyolefin homopolymers and copolymers. They are desirablyprepared from monoolefin monomers having but not limited to 2 to 7carbon atoms, such as ethylene, propylene, 1-butene, isobutylene,1-pentene, 1-hexene, 1-octene, 3-methyl-1-pentene, 4-methyl-1-pentene,5-methyl-1-hexene, mixtures thereof and copolymers thereof with(meth)acrylates and/or vinyl acetates. The polyolefins which can be usedin TPE formulations can be any desired grade of polypropylene includingisotactic polypropylene. Functionalized polypropylene is also desirableincluding, for example, polypropylene-maleic anhydride co-polymer.Polyolefins can be made by conventional Ziegler/Natta catalyst-systemsor by single-site catalyst-systems, or other polyolefin catalysttechnology in combination with various process technologies andsolutions.

Suitable olefinic rubbers of the monoolefin copolymer rubbers comprisenon-polar, rubbery copolymers of two or more α-monoolefins, preferablycopolymerized with at least one polyene, usually a diene. Saturatedmonoolefin copolymer rubber, for example ethylene-propylene copolymerrubber (EPM) can be used. However, unsaturated monoolefin rubber such asEPDM rubber is more suitable. EPDM is a terpolymer of ethylene,propylene and a non-conjugated diene. Satisfactory non-conjugated dienesinclude 5-ethylidene-2-norbomene (ENB); 1,4-hexadiene;5-methylene-2-norbomene (MNB); 1,6-octadiene; 5-methyl-1,4-hexadiene;3,7-dimethyl-1,6-octadiene; 1,3-cyclopentadiene; 1,4-cyclohexadiene;dicyclopentadiene (DCPD) and vinyl norbomene (VNB). Butyl rubbers arealso used in TPE formulation. The term “butyl rubber” includescopolymers of an isoolefin and a conjugated monoolefin, terpolymers ofan isoolefin with or without a conjugated monoolefin, divinyl aromaticmonomers and the halogenated derivatives of such copolymers andterpolymers. Another suitable copolymer within the olefinic rubber is acopolymer of a C₄₋₇ isomonoolefin, and a para-alkylstyrene. A furtherolefinic rubber used in TPE is natural rubber. The main constituent ofnatural rubber is the linear polymer cis-1,4-polyisoprene. Furthermorepolybutadiene rubber and styrene-butadiene-copolymer rubbers can also beused. Blends of any of the above olefinic rubbers can be employed,rather than a single olefinic rubber. Further suitable rubbers arenitrite rubbers. Examples of the nitrile group-containing rubber includea copolymer rubber comprising an ethylenically unsaturated nitrilecompound and a conjugated diene. Further, the copolymer rubber may beone in which the conjugated diene units of the copolymer rubber arehydrogenated. Specific examples of the ethylenically unsaturated nitrilecompound include acrylonitrile, α-chloroacrylonitrile,α-fluoroacrylonitrile and methacrylonitrile. Among them, acrylonitrileis particularly preferable. Other suitable rubbers are based onpolychlorinated butadienes such as polychloroprene rubber. These rubbersare commercially available under the trade names Neoprene® andBayprene®.

A commercially available thermoplastic elastomer (TPE) that showed somebenefits with the addition of PP-g-PEO is one formulated withoutplasticizers having a nominal density of 0.888 g/cm³ (ASTM D792-13) anda nominal composition of: 33.0 mol % propylene, 24.8 mol % ethylene, and42.2 mol % butylene.

Base polymeric materials with PP-g-PEO additive prepared with accordingto the process of the invention may be formed into useful articles bystandard forming methods known in the art, e.g., by blown filmextrusion, cast film extrusion, injection or blow molding, pelletizing,foaming, thermoforming, compounding in polymer melt form, or fiberspinning. For example, any technique discussed above in the embodimentsdescribing the melt processes can be used to prepare modified polymer,thereby forming various useful articles, depending on the type of meltprocessing technique used. For instance, blend may be used in makingfilms, such as blown or cast films. The techniques of blown filmextrusion and cast film are known to one skilled in the art in the areaof production of thin plastic films. Polymers with PP-g-PEO additive mayalso be used in coextruded films. The formation of coextruded blownfilms is known to one skilled in the art. The term “coextrusion” refersto the process of extruding two or more materials through a single diewith two or more orifices arranged such that the extrudates mergedtogether into a laminar structure, for instance, before chilling orquenching.

Turning to FIG. 1, a portion of an intravenous (IV) infusion kitcomprising tubing, an IV injection port, and connection is illustrated.A patient is connected to an IV source by means of an intravenous (IV)infusion kit. The kit comprises a length of tubing having connectors onthe ends and one or more injection sites or ports. The injection sitesor ports enable the injection of additional medications or the like viaa syringe or other IV source. The exemplary kit, as illustrated,comprises a needle 12 for insertion into a patient connected to tubing14 having a Y-site (connector) 16, and a tubing branch 18 for connectionto a source of IV fluid (not shown). The Y-site includes a conventionalIV injection site or port comprising an elastic plug and cap combination20 of Neoprene or the like on or over the end of a portion of theY-tube. The connection of an additional IV source for the injection of afluid is accomplished by inserting a conventional needle 22 through thesite or port 20 into the underlying tube. Embodiments of the presentinvention include tubing 14 being formed from a base polymericformulation comprising a polyolefin (e.g., polyethylene orpolypropylene) or a thermoplastic elastomer (TPE) to which is added anadditive comprising a polypropylene-poly(ethylene oxide) amphiphilicgraft copolymer (PP-g-PEO). The Y-site (connector) 16 may be formed froma material selected from the group consisting of: poly(methylmethacrylate) (PMMA), styrene maleic anhydride (SMA), polycarbonate(PC), and methyl methacrylate-acrylonitrile-butadiene-styrene (MABS).The tubing 14 is solvent-bonded to the Y-site (connector) 16.

General Procedure for Solvent Bonding

The solvent for treating outer surface of the tube is typically selectedfrom one or more hydrocarbons, such as cyclohexanone, cyclohexane,hexane, xylene, toluene, tetrahydrofuran (THF), ethyl acetate (EA) andmethyl ethyl ketone (MEK). Solvent treatment typically comprisesapplying the solvent to surface of the end portion of tube prior toinserting the end portion into the axial passage of the tubular body ofthe connector.

Solvent bonding is a method that allows two or more materials to bebonded together without the use of an adhesive. For example, Material“A” is a first component, such as tubing, that needs to be permanentlyaffixed (or bonded) to Material “B”, which may be a connector. BothMaterials “A” and “B” are dipped into a solvent that is suitable forprocessing of medical devices. The materials are then overlapped andsecured (e.g., by clamping) to form a bond area. The materials are keptin contact with each other for a time suitable to allow the overlappedarea to cure and form a bond.

Solvents suitable for assembling medical devices include but are notlimited to: cyclohexanone, methylene chloride, methyl ethyl ketone(MEK), tetrahydrofuran, acetone, 1, 2-dichloroethane, methyl benzene,tetrahydrofuran and blends of the solvents (50/50% methylenechloride/cyclohexanone, 50/50% or 80/20% MEK/cyclohexanone); bondingsolvent can be further loaded up to 25% by weight with the parentplastic or component of base formulation material (of the tube orconnector) to increase viscosity.

EMBODIMENTS

Various embodiments are listed below. It will be understood that theembodiments listed below may be combined with all aspects and otherembodiments in accordance with the scope of the invention.

Embodiment 1

A tubing for a medical device formed from a blend comprising: a basepolymeric formulation comprising at least a polymer or co-polymer ofethylene or propylene and excluding free poly(ethylene oxide); and anadditive comprising a polypropylene-poly(ethylene oxide) amphiphilicgraft copolymer (PP-g-PEO); the PP-g-PEO being present in the blend inan amount in the range of about 0.01 to about 5.0% by weight of theblend.

Embodiment 2

The tubing of embodiment 1, wherein the PP-g-PEO is according to Formula(I):

-   -   wherein R is hydrogen, alkyl, substituted alkyl, vinylic        substituted alkyl, hydrocarbyl, substituted hydrocarbyl, or        vinylic substituted hydrocarbyl group; the molar percentages of        grafted maleic anhydride units, m, is in the range from 2 to 10        mole percent; the molar values of propylene units, n, is in the        range from 98 to 90 mole percent, and p is in the range of 5 to        500 ethylene oxide units.

Embodiment 3

The tubing of one of embodiments 1 to 2, wherein the base polymericformulation comprises polyethylene, polypropylene, apolypropylene-maleic anhydride co-polymer, a polyethylene-polypropyleneco-polymer, a polyethylene- and/or polypropylene-containingthermoplastic elastomer (TPE), or combinations thereof.

Embodiment 4

The tubing of one of embodiments 1 to 3, wherein the base polymericformulation comprises a co-polymer of polyethylene and polypropylene.

Embodiment 5

The tubing of one of embodiments 1 to 3, wherein the polyethylene-and/or polypropylene-containing thermoplastic elastomer (TPE) comprisesat least 60 mol % total polyethylene and/or polypropylene.

Embodiment 6

The tubing of any one of embodiments 1 to 5, wherein the PP-g-PEO is aproduct of ethylene oxide ring-opening polymerization of apolypropylene-maleic anhydride co-polymer (PP-MA) having from 10-50weight percent of maleic anhydride.

Embodiment 7

A medical device comprising: a tubing comprising a polymeric blendcomprising a base polymeric formulation comprising at least a polymer orco-polymer of ethylene or propylene and excluding free poly(ethyleneoxide), and an additive comprising a polypropylene-poly(ethylene oxide)amphiphilic graft copolymer (PP-g-PEO) according to Formula (I); whereinthe PP-g-PEO is present in the blend in an amount in the range of about0.01 to about 5.0% by weight of the blend; and a connector bonded to thetubing; wherein the PP-g-PEO is effective to enhance bonding of thetubing to a connector.

Embodiment 8

The medical device of embodiment 7, wherein the base polymericformulation comprises polyethylene, polypropylene, apolyethylene-polypropylene co-polymer, a polyethylene- and/orpolypropylene-containing thermoplastic elastomer (TPE), or combinationsthereof.

Embodiment 9

The medical device of one of embodiments 7 to 8, wherein the basepolymeric formulation comprises a co-polymer of polyethylene andpolypropylene.

Embodiment 10

The medical device of one of embodiments 7 to 8, wherein thepolyethylene- and/or polypropylene-containing thermoplastic elastomer(TPE) comprises at least 60 mol % polyethylene and/or polypropylene.

Embodiment 11

The medical device of one of embodiments 7 to 10, wherein the PP-g-PEOis a product of ethylene oxide ring-opening polymerization of apolypropylene-maleic anhydride co-polymer (PP-MA) having from 10-50weight percent of maleic anhydride.

Embodiment 12

The medical device of one of embodiments 7 to 11, wherein the connectorcomprises a polar material.

Embodiment 13

The medical device of embodiment 12, wherein the polar material selectedfrom the group consisting of: poly(methyl methacrylate) (PMMA), styrenemaleic anhydride (SMA), polycarbonate (PC), and methylmethacrylate-acrylonitrile-butadiene-styrene (MABS).

Embodiment 14

The medical device of one of embodiment 7 to 13, wherein the connectoris solvent-bonded to the tubing.

Embodiment 15

A method of making a medical device comprising: obtaining apolypropylene-poly(ethylene oxide) amphiphilic graft copolymer(PP-g-PEO); combining the PP-g-PEO with a base polymeric formulationcomprising at least a polymer or co-polymer of ethylene or propylene andexcluding free poly(ethylene oxide) to form a blend, the PP-g-PEO beingpresent in the blend in an amount in the range of about 0.01 to about5.0% by weight of the blend; forming a tubing from the blend; bondingthe tubing to a connector in the presence of a solvent to form themedical device; wherein the PP-g-PEO is effective to enhance bonding ofthe tubing to a connector.

Embodiment 16

The method of embodiment 15, wherein ethylene oxide ring-openingpolymerization of a polypropylene-maleic anhydride co-polymer (PP-MA)having from 10-50 weight percent of maleic anhydride is used to form thePP-g-PEO, which is according to Formula (I).

Embodiment 17

The method of one of embodiments 15 to 16, wherein the base polymericformulation comprises polyethylene, polypropylene, apolyethylene-polypropylene co-polymer, a polyethylene- and/orpolypropylene-containing thermoplastic elastomer (TPE), or combinationsthereof.

Embodiment 18

The method of one of embodiments 15 to 17, wherein the base polymericformulation comprises a co-polymer of polyethylene and polypropylene.

Embodiment 19

The method of one of embodiments 15 to 17, wherein the polyethylene-and/or polypropylene-containing thermoplastic elastomer (TPE) comprisesat least 60 mol % polyethylene and/or polypropylene.

Embodiment 20

For any embodiment 1 to 19, wherein the PP-g-PEO has a dispersity indexin the range of 2 to 8.

Examples

PP-g-PEO graft copolymers tested herein are prepared according to themethods of U.S. Pat. No. 9,150,674. Specifically, polypropylene basedgraft copolymers were prepared from a polypropylene-maleic anhydrideco-polymer (PP-MA) starting material. Controlled ring-openingpolymerization was used to graft polymer side chains of ethylene oxideonto the polypropylene backbone to preparepolypropylene-graft-poly(ethylene oxide) (PP-g-PEO) copolymers havingfunctionalized side groups. Incorporation of hydrophilic poly(ethyleneoxide) (PEO) side-chains onto the polypropylene backbone resulted acopolymer with desired amphiphilic characteristics.

More specifically, the amphiphilic graft copolymers of the presentinvention were prepared in a two-step synthetic sequence. First, areduction reaction was performed on the PP-MA platform to prepare aniPP-diol copolymer, wherein the diol content is equal to the molarpercentage of the originally grafted maleic anhydride units. In thesecond step of the process, ethylene oxide ring-opening polymerizationwas performed on the iPP-diol copolymer to produce polypropylene basedgraft-copolymers.

The PP-g-PEO used in the following examples had a Brush Density of <1;an average EO units in Brush of 45.5; and a PEO content of ˜16 wt. %.

Example 1 Comparative

A first base polymer formulation based on a commercially availablethermoplastic elastomer (TPE) only was prepared. The TPE was analyzed by13C-NMR and FTIR to contain 33.0 mol % propylene, 24.8 mol % ethylene,and 42.2 mol % butylene. A 2.5″×0.5″ compression molded sample wasprepared from the first base polymer formulation at 200° C.

Example 2

Blends of varying PP-g-PEO graft copolymer content were made by meltmixing the PP-g-PEO graft copolymer with the first base polymerformulation of Example 1, the graft copolymer being present in amountsof 0.5 wt.-% (Example 2-1) and 5 wt.-% (Example 2-2) by weight of theblend. Exemplary components of medical devices were prepared bycompression molding as set forth in Example 1.

Example 3 Testing

Solvent Bonding Procedure.

Each of the exemplary components of medical devices according toExamples 1-2 (Material “A”) was solvent bonded to an exemplary secondcomponent of a medical device (Material “B”) made from polycarbonate(PC) (Makrolon® 2558). Materials “A” and “B” were both dipped into acyclohexanone solvent (for ˜5 seconds) and then overlapped (˜0.75-1 in)to create a bond area. Samples were then clamped together and allowed todry and harden for 48 hours.

Bonded strength was measured using Instron mechanical testinginstrument. Sample dimensions were measured to be 0.1 inches thick, 0.5inches wide, and a strain rate of 1.5 mm/min was applied using 5 kN loadcell. Samples were pulled until the bonded specimens “delaminated” andwere separated from one another. The maximum force achieved beforefailure was recorded for each bonded sample. Five samples were testedfor each composition and average values are reported in FIG. 2, whichshows Bond Strength (N) versus PP-g-PEO content. Modest increases inbond strength (11-17%) were achieved by Examples 2-1 and 2-2.

Example 4

Effect of polyethylene (PE) content on bond strength of the TPEaccording to Examples 1-2 was determined. Varying amounts of PE wereadded to the TPE in combination with 0.5 wt. % PE760-g-PEO4, which was apolyethylene-poly(ethylene oxide) amphiphilic graft copolymers(PE-g-PEO) was made according to U.S. Pat. No. 9,150,674 by First, ahydrolysis reaction was performed on an ethylene vinyl alcohol (EVA)platform whereby the acetate units were removed to produce ethylenevinyl alcohol copolymers (EVOH) and a methyl acetate co-product. Theacetate units were be removed by reaction with potassium methoxide andthe co-product methyl acetate will be removed by distillation. Theresultant polymeric potassium alkoxide was then used to initiateethylene oxide ring-opening polymerization (ROP). In the second step ofthe process, oxo-anion polymerization was performed on the copolymers ofethylene and vinyl acetate to produce polyethylene basedgraft-copolymers. The PE760-g-PEO4 had a Brush Density of 36 and anaverage EO units in Brush of 145.

Exemplary components of medical devices were prepared by compressionmolding as set forth in Example 1. These components were solvent bondedto samples of PC, MABS, and PMMA connector materials in accordance withExample 3 and tested for bond strength.

FIG. 3 provides a graph of bond strength (N) as averaged over thedifferent connector materials versus PE concentration in an exemplaryTPE base formulation, which used 0.5 wt.-% of PE-760-g-PEO-4 as theadditive in the base formulation. From FIG. 3, it appears that aco-polymer PE-g-PEO is more effective when TPE is polyethylene (PE) orpolypropylene (PP) rich. After addition of 10% PE to TPE bondingstrength of [TPE+0.5 wt. % PE-g-PEO] sample increased by 23%. Graftedcopolymers show solvent bonding strength increase for PP and PE rich TPEsamples; suggesting that co-polymers are more effective in TPEscontaining at least 30-40 mol % or higher of each of propylene (C3)and/or ethylene (2) single component (TPE should be C3 or C2 rich).

From this, it is concluded that a TPE is polyethylene (PE) orpolypropylene (PP) rich will also be more effective when used with aco-polymer PP-g-PEO as disclosed herein. A preferred base polymericformulation contains 60-100 mol % (or 65-100 mol % or even 70-100 mol %)total of polyethylene and polypropylene.

Example 5 Comparative

A second base polymer formulation based on a commercially availablepolypropylene (PP) (Homopolymer PH592) only was prepared. Exemplarycomponents of medical devices were prepared by compression molding asset forth in Example 1.

Example 6

Blends of varying PP-g-PEO graft copolymer content were made by meltmixing the PP-g-PEO graft copolymer with the second base polymerformulation of Example 5, the graft copolymer being present in amountsof 0.5 wt.-% (Example 6-1) and 5 wt.-% (Example 6-2) by weight of theblend. Exemplary components of medical devices were prepared bycompression molding as set forth in Example 1.

Example 7 Testing

The solvent bonding procedure and testing according to Example 3 wereconducted for the exemplary components of medical devices according toExamples 5-6 (Material “A”), which were solvent bonded to an exemplarysecond component of a medical device (Material “B”) made frompolycarbonate (PC) (Makrolon® 2558).

Average values are reported in FIG. 4, which shows Bond Strength (N)versus PP-g-PEO content. A significant increase in bond strength wasachieved by Examples 6-1 (54%) and 6-2.

Example 8 Comparative

A third base polymer formulation based on a commercially availablelinear low density polyethylene (LLDPE) (Dowlex™ 2045.01 G) only wasprepared. Exemplary components of medical devices were prepared bycompression molding as set forth in Example 1.

Example 9

Blends of varying PP-g-PEO graft copolymer content were made by meltmixing the PP-g-PEO graft copolymer with the third base polymerformulation of Example 8, the graft copolymer being present in amountsof 0.5 wt.-% (Example 9-1) and 5 wt.-% (Example 9-2) by weight of theblend. Exemplary components of medical devices were prepared bycompression molding as set forth in Example 1.

Example 10 Testing

The solvent bonding procedure and testing according to Example 3 wereconducted for the exemplary components of medical devices according toExamples 8-9 (Material “A”), which were solvent bonded to an exemplarysecond component of a medical device (Material “B”) made frompolycarbonate (PC) (Makrolon® 2558).

Average values are reported in FIG. 5, which shows Bond Strength (N)versus PP-g-PEO content. A significant increase in bond strength wasachieved by Examples 9-1 (30%) and 9-2.

Reference throughout this specification to “one embodiment,” “certainembodiments,” “one or more embodiments” or “an embodiment” means that aparticular feature, structure, material, or characteristic described inconnection with the embodiment is included in at least one embodiment ofthe invention. Thus, the appearances of the phrases such as “in one ormore embodiments,” “in certain embodiments,” “in one embodiment” or “inan embodiment” in various places throughout this specification are notnecessarily referring to the same embodiment of the invention.Furthermore, the particular features, structures, materials, orcharacteristics may be combined in any suitable manner in one or moreembodiments.

Although the invention herein has been described with reference toparticular embodiments, it is to be understood that these embodimentsare merely illustrative of the principles and applications of thepresent invention. It will be apparent to those skilled in the art thatvarious modifications and variations can be made to the method andapparatus of the present invention without departing from the spirit andscope of the invention. Thus, it is intended that the present inventioninclude modifications and variations that are within the scope of theappended claims and their equivalents.

What is claimed is:
 1. A tubing for a medical device formed from a blendcomprising: a base polymeric formulation comprising at least a polymeror co-polymer of ethylene or propylene and excluding free poly(ethyleneoxide); and an additive comprising a polypropylene-poly(ethylene oxide)amphiphilic graft copolymer (PP-g-PEO); the PP-g-PEO being present inthe blend in an amount in the range of about 0.01 to about 5.0% byweight of the blend.
 2. The tubing of claim 1, wherein the PP-g-PEO isaccording to Formula (I):

wherein R is hydrogen, alkyl, substituted alkyl, vinylic substitutedalkyl, hydrocarbyl, substituted hydrocarbyl, or vinylic substitutedhydrocarbyl group; the molar percentages of grafted maleic anhydrideunits, m, is in the range from 2 to 10 mole percent; the molar values ofpropylene units, n, is in the range from 98 to 90 mole percent, and p isin the range of 5 to 500 ethylene oxide units.
 3. The tubing of claim 1,wherein the base polymeric formulation comprises polyethylene,polypropylene, a polypropylene-maleic anhydride co-polymer, apolyethylene-polypropylene co-polymer, a polyethylene- and/orpolypropylene-containing thermoplastic elastomer (TPE), or combinationsthereof.
 4. The tubing of claim 3, wherein the base polymericformulation comprises a co-polymer of polyethylene and polypropylene. 5.The tubing of claim 3, wherein the polyethylene- and/orpolypropylene-containing thermoplastic elastomer (TPE) comprises atleast 60 mol % total polyethylene and/or polypropylene.
 6. The tubing ofclaim 1, wherein the PP-g-PEO is a product of ethylene oxidering-opening polymerization of a polypropylene-maleic anhydrideco-polymer (PP-MA) having from 10-50 weight percent of maleic anhydride.7. The tubing of claim 1, wherein the PP-g-PEO has a dispersity index inthe range of 2 to
 10. 8. A medical device comprising: a tubingcomprising a polymeric blend comprising a base polymeric formulationcomprising at least a polymer or co-polymer of ethylene or propylene andexcluding free poly(ethylene oxide), and an additive comprising apolypropylene-poly(ethylene oxide) amphiphilic graft copolymer(PP-g-PEO) according to Formula (I):

wherein R is hydrogen, alkyl, substituted alkyl, vinylic substitutedalkyl, hydrocarbyl, substituted hydrocarbyl, or vinylic substitutedhydrocarbyl group; the molar percentages of grafted maleic anhydrideunits, m, is in the range from 2 to 10 mole percent; the molar values ofpropylene units, n, is in the range from 98 to 90 mole percent, and p isin the range of 5 to 500 ethylene oxide units; wherein the PP-g-PEO ispresent in the blend in an amount in the range of about 0.01 to about5.0% by weight of the blend; and a connector bonded to the tubing;wherein the PP-g-PEO is effective to enhance bonding of the tubing to aconnector.
 9. The medical device of claim 8, wherein the base polymericformulation comprises polyethylene, polypropylene, apolyethylene-polypropylene co-polymer, a polyethylene- and/orpolypropylene-containing thermoplastic elastomer (TPE), or combinationsthereof.
 10. The medical device of claim 8, wherein the base polymericformulation comprises a co-polymer of polyethylene and polypropylene.11. The medical device of claim 8, wherein the polyethylene- and/orpolypropylene-containing thermoplastic elastomer (TPE) comprises atleast 60 mol % polyethylene and/or polypropylene.
 12. The medical deviceof claim 8, wherein the PP-g-PEO is a product of ethylene oxidering-opening polymerization of a polypropylene-maleic anhydrideco-polymer (PP-MA) having from 10-50 weight percent of maleic anhydride.13. The medical device of claim 8, wherein the connector comprises apolar material.
 14. The medical device of claim 13, wherein the polarmaterial selected from the group consisting of: poly(methylmethacrylate) (PMMA), styrene maleic anhydride (SMA), polycarbonate(PC), and methyl methacrylate-acrylonitrile-butadiene-styrene (MABS).15. The medical device of claim 8, wherein the connector issolvent-bonded to the tubing.
 16. A method of making a medical devicecomprising: obtaining a polypropylene-poly(ethylene oxide) amphiphilicgraft copolymer (PP-g-PEO); combining the PP-g-PEO with a base polymericformulation comprising at least a polymer or co-polymer of ethylene orpropylene and excluding free poly(ethylene oxide) to form a blend, thePP-g-PEO being present in the blend in an amount in the range of about0.01 to about 5.0% by weight of the blend; forming a tubing from theblend; bonding the tubing to a connector in the presence of a solvent toform the medical device; wherein the PP-g-PEO is effective to enhancebonding of the tubing to a connector.
 17. The method of claim 16,wherein ethylene oxide ring-opening polymerization of apolypropylene-maleic anhydride co-polymer (PP-MA) having from 10-50weight percent of maleic anhydride is used to form the PP-g-PEO, whichis according to Formula (I):

wherein R is hydrogen, alkyl, substituted alkyl, vinylic substitutedalkyl, hydrocarbyl, substituted hydrocarbyl, or vinylic substitutedhydrocarbyl group; the molar percentages of grafted maleic anhydrideunits, m, is in the range from 2 to 10 mole percent; the molar values ofpropylene units, n, is in the range from 98 to 90 mole percent, and p isin the range of 5 to 500 ethylene oxide units.
 18. The method of claim16, wherein the base polymeric formulation comprises polyethylene,polypropylene, a polyethylene-polypropylene co-polymer, a polyethylene-and/or polypropylene-containing thermoplastic elastomer (TPE), orcombinations thereof.
 19. The method of claim 18, wherein the basepolymeric formulation comprises a co-polymer of polyethylene andpolypropylene.
 20. The method of claim 18, wherein the polyethylene-and/or polypropylene-containing thermoplastic elastomer (TPE) comprisesat least 60 mol % polyethylene and/or polypropylene.